Heat-activable polyurethane sheet

Abstract

The use of a film for adhesively bonding two substrates, wherein the film comprises a layer which is composed of more than 30% by weight of a heat-activatable polyurethane (PU layer for short).

1 . The use of a film for adhesively bonding two substrates, wherein the film comprises a layer which is composed of more than 30% by weight of a heat-activatable polyurethane (PU layer for short). 
   
   
       2 . The use according to  claim 1 , wherein the polyurethane is synthesized from more than 60% by weight of synthesis components selected from diisocyanates, polyesterdiols, polyetherdiols or mixtures thereof. 
   
   
       3 . The use according to  claim 1 , wherein the polyurethane is synthesized from more than 10% by weight of polyesterdiols. 
   
   
       4 . The use according to  claim 1 , wherein the polyurethane has a melting point in the range from 30 to 150° C. 
   
   
       5 . The use according to  claim 1 , wherein the PU layer comprises a crosslinker for the polyurethane. 
   
   
       6 . The use according to  claim 1 , wherein the PU layer comprises 0.0001 to 0.1 mol of carbodiimide groups to 100 g of polyurethane. 
   
   
       7 . The use according to  claim 1 , wherein the PU layer besides the polyurethane comprises if appropriate further polymeric binders, examples being polymers obtainable by free-radical addition polymerization, and auxiliaries, examples being wetting agents. 
   
   
       8 . The use according to  claim 1 , wherein the film is composed of the PU layer and the PU layer is coated if appropriate on one or both sides with a pressure-sensitive adhesive or primer or both. 
   
   
       9 . The use according to  claim 1 , wherein the film is composed of two PU layers with a carrier layer in between, and the outside PU layers are coated if appropriate with pressure-sensitive adhesive or with a primer. 
   
   
       10 . The use according to  claim 1 , wherein the thickness of the film is 1 μm to 3 mm. 
   
   
       11 . The use according to  claim 1 , wherein the film is used as a laminating adhesive. 
   
   
       12 . A method of laminating moldings to any desired laminates, which comprises
 a) depositing on the molding a film according to  claim 1  and a laminate to be laminated on, so that the film is located between the molding and the laminate,   b) heat-activating the film, by means of infrared radiation for example, and   c) adhesively bonding the molding to the laminate.   
   
   
       13 . The method according to  claim 12 , which is carried out continuously. 
   
   
       14 . The method according to  claim 12 , which is carried out under reduced pressure, in a thermoforming operation for example, or under elevated pressure. 
   
   
       15 . A product, in particular a laminated molding, obtainable through use according to  claim 1 . 
   
   
       16 . A film composed of a PU layer according to  claim 1 , the PU layer being coated if appropriate on one or both sides with a pressure-sensitive adhesive or primer or both. 
   
   
       17 . A film composed of two PU layers according to  claim 1  and of a carrier layer in between, the outside PU layers being coated if appropriate with pressure-sensitive adhesive or with a primer or with both. 
   
   
       18 . A product, in particular a laminated molding, obtainable through the method according to  claim 12 .